Merged revisions 222298 via svnmerge from

https://origsvn.digium.com/svn/asterisk/trunk

........
  r222298 | jpeeler | 2009-10-06 14:24:59 -0500 (Tue, 06 Oct 2009) | 9 lines
  
  Fix crash during destruction of second channel when variable set with setvar.
  
  The setvar line in chan_dahdi.conf is shared among all the channels, so make
  sure to only free the resources only when the last channel is destroyed.
  
  (closes issue #15899)
  Reported by: tzafrir
........


git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/1.6.2@222304 65c4cc65-6c06-0410-ace0-fbb531ad65f3

channels/chan_dahdi.c

@@ -3859,8 +3859,9 @@ static void destroy_dahdi_pvt(struct dahdi_pvt **pvt)
 		ast_smdi_interface_unref(p->smdi_iface);
 	if (p->mwi_event_sub)
 		ast_event_unsubscribe(p->mwi_event_sub);
-	if (p->vars)
+	if (p->vars && iflist && !iflist->next) {
 		ast_variables_destroy(p->vars);
+	}
 	ast_mutex_destroy(&p->lock);
 	dahdi_close_sub(p, SUB_REAL);
 	if (p->owner)